From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753489AbaEFVW0 (ORCPT ); Tue, 6 May 2014 17:22:26 -0400 Received: from hqemgate15.nvidia.com ([216.228.121.64]:12478 "EHLO hqemgate15.nvidia.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751272AbaEFVWT (ORCPT ); Tue, 6 May 2014 17:22:19 -0400 X-PGP-Universal: processed; by hqnvupgp07.nvidia.com on Tue, 06 May 2014 14:12:05 -0700 From: Christopher Freeman To: , , , CC: , , , Christopher Freeman Subject: [PATCH v1 3/3] dma: tegra: avoid int overflow for transferred count Date: Tue, 6 May 2014 14:22:23 -0700 Message-ID: <1399411343-12222-4-git-send-email-cfreeman@nvidia.com> X-Mailer: git-send-email 1.7.9.5 In-Reply-To: <1399411343-12222-1-git-send-email-cfreeman@nvidia.com> References: <1399411343-12222-1-git-send-email-cfreeman@nvidia.com> MIME-Version: 1.0 Content-Type: text/plain Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org bytes_transferred will overflow during long audio playbacks. Since the driver only ever consults this value modulo bytes_requested, store the value modulo bytes_requested. Signed-off-by: Christopher Freeman --- drivers/dma/tegra20-apb-dma.c | 20 ++++++++++++-------- 1 file changed, 12 insertions(+), 8 deletions(-) diff --git a/drivers/dma/tegra20-apb-dma.c b/drivers/dma/tegra20-apb-dma.c index 094e97d..e1b80a4 100644 --- a/drivers/dma/tegra20-apb-dma.c +++ b/drivers/dma/tegra20-apb-dma.c @@ -583,7 +583,9 @@ static void handle_once_dma_done(struct tegra_dma_channel *tdc, tdc->busy = false; sgreq = list_first_entry(&tdc->pending_sg_req, typeof(*sgreq), node); dma_desc = sgreq->dma_desc; - dma_desc->bytes_transferred += sgreq->req_len; + dma_desc->bytes_transferred = (dma_desc->bytes_transferred + + sgreq->req_len) % + dma_desc->bytes_requested; list_del(&sgreq->node); if (sgreq->last_sg) { @@ -613,7 +615,9 @@ static void handle_cont_sngl_cycle_dma_done(struct tegra_dma_channel *tdc, sgreq = list_first_entry(&tdc->pending_sg_req, typeof(*sgreq), node); dma_desc = sgreq->dma_desc; - dma_desc->bytes_transferred += sgreq->req_len; + dma_desc->bytes_transferred = (dma_desc->bytes_transferred + + sgreq->req_len) % + dma_desc->bytes_requested; /* Callback need to be call */ if (!dma_desc->cb_count) @@ -762,8 +766,10 @@ static void tegra_dma_terminate_all(struct dma_chan *dc) if (!list_empty(&tdc->pending_sg_req) && was_busy) { sgreq = list_first_entry(&tdc->pending_sg_req, typeof(*sgreq), node); - sgreq->dma_desc->bytes_transferred += - get_current_xferred_count(tdc, sgreq, wcount); + sgreq->dma_desc->bytes_transferred = + (sgreq->dma_desc->bytes_transferred + + get_current_xferred_count(tdc, sgreq, wcount)) % + sgreq->dma_desc->bytes_requested; } tegra_dma_resume(tdc); @@ -838,8 +844,7 @@ static enum dma_status tegra_dma_tx_status(struct dma_chan *dc, list_for_each_entry(dma_desc, &tdc->free_dma_desc, node) { if (dma_desc->txd.cookie == cookie) { residual = dma_desc->bytes_requested - - (dma_desc->bytes_transferred % - dma_desc->bytes_requested); + dma_desc->bytes_transferred; dma_set_residue(txstate, residual); ret = dma_desc->dma_status; spin_unlock_irqrestore(&tdc->lock, flags); @@ -859,8 +864,7 @@ static enum dma_status tegra_dma_tx_status(struct dma_chan *dc, typeof(*first_entry), node); residual = dma_desc->bytes_requested - - (dma_desc->bytes_transferred % - dma_desc->bytes_requested); + dma_desc->bytes_transferred; /* hw byte count only applies to current transaction */ if (first_entry && -- 1.7.9.5